University of Louisville spokesperson John Drees said the crowd was dispersed because a fire department arson officer was attacked while trying to break up an “incident,” the report said. Drees confirmed to the Courier Journal that police used pepper spray and tear gas to help disperse the crowd.

Reporters on the scene described being hit by pepper ball pellets and being choked by the released spray. Tear gas canisters were also dispersed.

Campus police, working with Louisville police and sheriff's deputies, reported just 10 arrests and three injuries, The Associated Press reports.

The armored carrier was brought in and order was restored before 1:30 a.m. central time.